MY 4W ABS LIGHT IS ON AND MY CAR IS MAKING A

I was driving my car at a normal speed and everything was fine. I stopped, turned off car, and got back in. Once I started to drive my 4W ABS light came on. So I pulled over, turned off the car and popped the hood. The light went off, but there was a hissing noise. I turned back on the car and the light came right back on and the hissing noise never stopped. Its been 2 hours and the noise is still there and when I turn the car on and put it in Drive the light comes back on. HELP! Please.

Well now my car won't start. The hissing noise continued thoughout the night. I took the battery out and took it to auto zone to be recharged. They rechared the battery and I put it back in my car. It still won't start. Now what should I do?